Tyson Gay (L, orange shirt) besting Jamaica's Asafa Powell (red) in the 100 meters at the Diamond League meet July 4 in Lausanne, Switzerland. Both confirmed Sunday they have tested positive for banned substances.

Tyson Gay (L, orange shirt) besting Jamaica's Asafa Powell (red) in the 100 meters at the Diamond League meet July 4 in Lausanne, Switzerland. Both confirmed Sunday they have tested positive for banned substances.